Electric switch



March 28, 1939. J, w, ow s 2,152,496

ELECTRIC SWITCH I Filed Sept. 1?, 1.93"!

Inventor:

Joseph W. Owens,

by li i Att orney.

Patented Mar. 28,1939

UNITED STATES PATENT osrics Joseph W. Owens, Schenectady,

to General Electric Company,

New York Application September Claims.

My invention relates to electric switches, more particularly to switches provided with one or more bridging contact members, and has for its object a simple and reliable, quickly detachable sup- 5 port for a bridging contact member.

My invention is especially useful in the construction of switches of the bridging type of comparatively low amperage capacity, such for example, as may be used in the controlling of small motors or as interlock contacts carried by a large switch or contactor. Such bridging contacts are often supported on an elongated bar or post, the bridging member being biased toward the outer end of the post by means of a. suitable spring. In accordance with my invention, Iprovide a post of special shape with special means for slidably locking the bridgingmember thereon. More specifically, I provide a post which is in the shape of a strap having the outer end bent over to form an abutment against which the bridging contact is held by a suitable spring, the strap being provided with a slot and the bridging contact with an interlocking tongue wher by it is slidably held on the strap. For a more complete understanding of my invention, reference should be had to the drawing,

Fig. l of which is a front elevation view of a brid ing contact embodying my invention; Fig. 21s a sectional view of Fig. 1 along the line 2-2 looking in the direction of the arrows; Fig. 3 is a sectional view of Fig. 1 along the line 3-3 looking in the direction of the arrows; while Fig. 4 is a disassembled view showing the parts with the exception of the spring.

In carrying out my invention in one form, I provide a supporting bar or post in for the bridging contact II which is in the shape of a strap and made of a suitable metal such as soft steel. As shown in Figs. 1 and 2, the upper end of the support III is bent over to form a laterally extending projection, the outer end 12 of which forms a seat for the bridging contact which is held against this seat by a suitable helical spring I3.

The bridging contact is secured to the support so as to be slidable longitudinally thereof by means of an interlocking projection or extension I! extending laterally from its middle which cooperates with a specially shaped opening or slot.

in the support. As shown, this opening comprises an inverted T-shaped slot l5 formed by a slot l6 extending lengthwise of the support and terminating at its upper end, as viewed in Figs. 1, 2

and 3, at a point adjacent the extension 12.

Another slot I'I extending crosswise at the lower 66 end of the slot 16 forms the head of the T.

N. Y., assignma corporation of 17, 1937, Serial No. 164,365

This cross slot I I is somewhat longer than the width of the projection l4 so that the projection can be slipped freely into the slot H. In the edges of the extension H are slots or notches l8 and I! which are somewhat wider than the thickness of' the material of the support and deep enough so that the metal of the projection at that point is somewhat narrower than the width of the slot 16. Thus the projection M can be inserted freely in the slot l1 and then slid longitudinally along the support to the upper end as seen in Figs, 1 and 2, the end of the projection l4 coming to rest against the upper wall of the slot [6, which forms a stop, and the middle of the bridging contact coming to rest against the seat I2. The spring 13 bears against the middle portion of the bridging contact, member between its point of engagement with the upper end wall of the slot l6 and the seat I! so as to hold the bridging member in engagement with these points. If desired, the spring may be inserted after the bridging member 'has been slipped in place or the spring may be put in position and compressed to permit the projection I to be slipped into the cross slot ll after which the spring forces the bridging member to the position shown in Figs. 1, 2 and 3.

I have found that this support for bridging contact is simple and inexpensive, has few parts and is easy to assemble. At the same time, the bridging member is held securely on the support. It is, for example, impossible to accidentally release the bridging member by the force of, compressed air when the switch is being cleaned, which I have found to occur with various other quickly detachable supporting means. The support l0 and bridging contact member ll may, if desired, be stamped from a suitable material such as soft steel.

I have shown the support Ill secured at its lower end to a supporting member 20 made of insulating material. The lower end of the support is provided with shoulders 2| and 22 which engage the sides of an aperture in the support 20 and two pro- .jections on the lower end extend through the aperture and into suitable holes provided for them in a cross plate 23. The pins are riveted over in the plate 23 to firmly secure thesupport ll in place.

I contemplate that the insulating support 2! will be secured to an operating member of a suitable switch as by means of a threaded bushing 24. Thus the bridging contact may serve as an interlock contact on a magnetically operated switch or contactor or it may serve as the main switchin: contact.

The spring I! is held in place by a protuberance 25 which may be formed in the bridging member by suitably punching the material out at the lower side. The lower end of the spring is held in place by a similar projection 26 on an extension of-the support 20.

On opposite sides of the spring are walls 21 and 28 formed oi. insulating material and forming a part of the support 20 which may be made of a suitable molded electrically insulating material. These walls 27 and 28 are of such height that the bridging member when assembled cannot be turned around or twisted far enough to slip out of the slot l6, one end of the bridging member engaging one or the other of the walls or barriers. Furthermore, the bridging contact cannot be slid downward longitudinally by simply pressing on its two extreme ends forming the contact making and breaking surfaces. The widths oi the slots l8 and I9 are great enough to permit the bridging contact to be depressed a considerable distance by engagement of its outer ends but the inner end of the locking projection I4 is held upward by the spring. The bridging contact is eventually brought to rest by engagement of the sides of the support III with the opposite walls 01' the slot l8 and I9. Of

course the contact can be depressed as a whole for removal or for other purposes.

While I have shown a particular embodiment of my invention, it will be understood, of course, that I do not wish to be limited thereto since many modifications may be made, and I therefore contemplate by the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In an electric switch, a supporting member, an elongated support having one end secured to said supporting member and its other end provided with 'a transversely extending projection, a contact member normally resting against the end oi said projection, an extension on said contact member engaging said support and slidably connected to said support, a stop on said support, and a spring having one end bearing on said supporting member and its other end in engagement with said extension on said contact member at a point between said stop and the end of said projection to thereby hold said contact member against said stop and said projection.

2. In an electric switch, a supporting member, an elongated support secured at one end to said supporting member having a substantially straight portion extending from said supporting member and a transverse projection on its other end, a contact member normally in engagement with the end of said projection, an extension on said contact member extending to said straight portion, a sliding connection between said extension and said straight portion, a stop on said straight portion, and a spring having one end bearing on said supporting meember and its other end bearing on said extension at a point between said stop and the end of said projection to thereby hold said contact member in engagement with said stop and the end of said projection.

3. In an electric switch, a supporting member, I

an elongated support secured at one end to said supporting member having a substantially straight portion extending from said supporting member and a transverse projection on its other end, a bridging contact member normally held with its middle portion in engagement with the end of said projection, a lateral extension on said bridging member extending from its middle portion to said straight portion, a sliding connection between the end of said extension and said straight portion, said connection providing a stop for said extension on said straight portion adjacent said projection, and a am having one end bearing on said supporting member and its other end bearing on said extension at a point between said straight portion and said bridging member to thereby hold said bridging member in engagement with said stop and the end of said transverse projection.

4. In an electric switch, an elongated support, a transverse projection on one end of said support, said support being provided with two slots, one extending lengthwise thereof and terminating at one end adjacent said projection and the other slot extending across said support at the other end of said first slot, a contact member having an interlocking extension adapted to be inserted in said second slot and provided with a notch in each side to receive the walls of said first slot whereby said contact member can be moved along said support into engagement with said projection, and a spring for holding said contact member in engagement with said projection.

5. In an electric switch, an elongated support, a transverse projection on one end of said support, said support being provided with two slots, one extending lengthwise thereof and terminating at one end adjacent said projection and the other slot extending across said support at the other end of said first slot, a bridging contact member having a central lateral extension forming an interlocking portion adapted to be inserted in said second slot and provided with a notch ineach side to receive the walls of said JOSEPH W. OWENS. 

